Sun screen with plastic warp



April 3,, 1951 w. B. EWlNG ET'AL SUNSCREEN WITH PLASTIC WARP Filed June 7, 1947 INVENTOR. WALKLEY B EWING JGHN J. GREBE Patented Apr. 3, 1951 2 UNITED STATES PATENT OFFICE SUN SCREEN'WITH PLASTIC WARP Walkley B. Ewing, Grand Haven, Mich., and John J. Grebe, Oak Ridge, Tenn., assignors to Ewing Development Company, Bay City, Mich, a corporation of Michigan Application J nine 7, 1947, Serial No. 753,206

2 Claims. I

This invention relates generally to a screen structure adapted for preventing the passage of insects and for preventing the passage of the suns direct radiation at normalangles of incidence during the heat of the day, and relates more particularly to an improvement in the vertical, or warp wires thereof. a

Since the inception of the combination insect and sun screen, many attempts have been made equipment which limit, in varying degrees, the output of such screen. Therefore, it becomes apparent that improvements in a combination sun and insect screen are desired which will materially reduce the cumbersome and time-consuming operations resulting from the use of the present types of warp wires.

In many of these known types of combination to eliminate or reduce those operations, constiinsect and sunscreen fabrics there is, unfortuting essential steps in the production of the tunately, little or no resilience. Hence, it is not present types of such screen, which are both only difiicult to obtain a taut surface when a cumbersome and time consuming. Paramount large section of the sunscreen is framed, but also among such problems is that which concerns the it is virtually impossible even in smaller Secmanner in which the weft wires, or horizontal tions to restore said fabric to a taut surface after louvers, are engaged and held in spaced relationit has become bagged out due to normal hard ship with respect to each other by means of usage. suitable warp or vertical wires. It has also long been recognized that where a Another problem in the fabrication of sunsunscreen is raised and lowered on a roll in the screen concerns the electrolytic corrosion which manner of a shade, it is desired to impart elasattacks those bi-metallic sunscreens in which ticity to said sunscreen in order to render it the warp and weft wires are made from discapable of use on arollof small diameter. Howsimilar metals, such as aluminum and bronze. ever, since sunscreen, due to its twofold purpose, The moisture of the atmosphere provides the does not lend itself readily to elasticity in a electrolyte which, given time to act, will not only horizontal direction, any resilience in the sundiscolor but also destroy the said'bi-metallic type screen fabric must arise out of an elastic charscreens. Although the bi-metallic construction acteristic in the warp or vertical wires. might otherwise be found advantageous, the said Attempts have been made to crimp, corrugate electrolytic corrosion precludes the successful or otherwise deform metallic warp wires in an use of this construction. Hence it also becomes 3 effort to produce elasticity therein. The difdesirable to provide a sunscreen construction in ficulties and expenses encountered, however, which dissimilar materials may be used for the make such methods impractical. warp and weft wires, in orderto effect cost or A further problem, arising out of the use of other advantages, without encountering the said the conventional, metallic warp or vertical wires undesirable effects. in the combination insect and sunscreen, in-

Those principal types of vertical wire construovolves their interference with the maximum free tions presently in conventional use include: the passage of light between the horizontal louvers double, metallic wire type in which a plurality of the said sunscreen fabric. Since light interof wires in pairs cross or interlock between each ference has always constituted an undersirable metallic louver wire, examples of which are dis- 40 aspect in any kind of screen, it is apparent that closed in the W. B. Ewing Patent No. 2,194,222 any reduction in such obstruction to light pasand J. J. Grebe Patent No. 2,078,940; the single sage is extremely desirable. metallic warp wire type in which the said louvers Accordingly, a primary object of this invenare secured, such as by brazing or soldering, to tion is to provide a combined sun and insect a plurality of uniformly spaced warp wires, an screen, of the general type disclosed by the aboveexample of which is disclosed in our abandoned mentioned patents, which will embody substanco-pending application, entitled Screen, Serial tially all the advantages thereof, but which will No. 736,600, filed March 22, 1947; and the inparticularly reduce the aforementioned time tegral wire type in which the said warp wires, consuming operations incident to the construc-, as well as the louvers associated therewith, are tion and materials presently used in said screens.

stamped, punched, or otherwise shaped and formed, from sheets of suitable metallic materials, an example of which is disclosed in the J. J. Grebe et al. Patent No. 2,319,225.

Fabrication of each of the above-mentioned A further object of this invention is to provide improved warp wire means in a combined sun and insect screen as aforesaid which is made of such material that it can be readily bonded or softened and adhered to other similar or dis-.

similar materials by means of moderate applica- V tions of heat or suitable solvents.

screen while decreasing both the cost and the.

problems normally involved therein.

A further object of this invention is to provide improved warp wire means as aforesaid whereby the elasticity of said sunscreen fabricimthe:

direction of said warp wires will be substantially increased.

A further object of this invention .is.:to'pro vides.

an improved warp wire means as aforesaid whereby the interference thereby with the free passage of light between the: said? horizontal louvers may be substantially reduced.

Other objects and purposes of this invention will become apparent to persons familiar with this type of equipment-upon referring to the accompanying drawings and'uponreading the fol lowing specification.

In meeting the aforesaid objects and purposes, as well as others incidental thereto and associated therewith, we have provided improvements in the vertical 'or Warp wires of a'combination type sun and insect screen. The said horizontal louvers, which may beof any suitable convenient type-such'as-disclosed in theE-Wlllg Patent No. 2,194,222, are supported by pairs of vertical wires or threads which are made of a type of material, usually an organic thermoplastic, which is longitudinally elastic and. which becomes pliable and cohesive when exposed toeither moderate heating or treated with a suitable solvent.

The louver wires lie between each saidpair of resilient, uniformly disposed warp threads so that the planes established by each pair are substantially perpendicular to the plane of the entire screen. Each warp thread of each of 'said'pairs meets the other thereof between each louver where said threads are bonded to each other, as

aforesaid, by means of appropriate treatment with heat or a solvent. The said louvers or horizontal wires are held uniformlydisposed and substantially parallel with respect toeachother by said pairs of vertical threads;-

For-convenience, in the following description" and claims, the sunscreen panel wil be assumed to be in a vertical position with the long axis ofthe louvers extending in a horizontal'position. It will be understood that'this is for convenience of language only and implies no'limitation to'the position in which such screen may be used orto the. applicability of the claims when'such screen is used in other than the vertical position described and illustrated;

For illustrations of the: improved. sunscreen; attention is directed to the 'accompanyingdrawings in which:

Figure 1 is the front elevation view of a sunscreen employing a preferredembodiment of the improved warp wire.

Figure 2 is a broken sectional view taken along the line II'-II in Figure 1 or Figure 3.

Figure 3 is a fragmentary sectionalview'of" Figure-1 taken along. the line III-III;

Figure 4 is essentiallythe same type sectional" viewaas taken-along the line III--III of .Figure 1, but illustrates a variation in warp wire.

Figure 5 is a sectional viewofthevariation shown in Figure 41 takenalong the-line V-V' therein.

As illustrated in Figure 1, the combination sun and insect screen panel II] comprises a plurality of uniformly disposed, parallel, horizontal louvers l I held in fixed angular relationship with respect to the plane of the screen by means of a plurality of the improved warp wires I2 to which this inventionirelates; Each said..improved=warp wire I2 may be comprised of a pair of cooperating warp threads I3 and I4, hereinafter described in detail, which lie substantially within a single plane on-ropposing sides of said plurality of horizontal louvers II and are brought together and suitably; engaged toeach other at points between said louvers; The. said horizontal louvers II may be. of any, convenient, conventional type presently in use, butare preferably of metal, such as aluminumaorrbronze, and of elongated crosssectionthroughout their length, such as is illustratedin Figure 3 and is disclosed in the aforementioned Ewing Patent No. 2,194,222. Inasmuch as-horizontal louvers-of this general type are common knowledge in the art, further de scription thereof will be omitted.

The said cooperating, contacting warp threads I3 and Mmay be of any desired material, whichis slightly resilient and which can be softened by the application of moderateheat, such as not in ous or cellulosic substance, usually but not neces-' sarily thermoplastic, hereinafter for convenience referred to generally as a plastic. Specific examples of suitable plastic materials include nylon, ethyl acetate, methacrylate; and th'evinyl resins. It is obvious, of course, that the temperature, underrwhich the plastic substance becomes pliableand/or cohesive, must be substantially higher than the anticipated maximum temperature produced'b'y the direct radiation of the'sun in whatever location the said sun screen is intended or likely to be used.

As illustrated'in Figures 2 and 5 said" warp threads may have any shape and/or cross-sectional sizeand contour as may be required, providing onlythat the combined' tensile strengths ofeach said'pair of warp threads constituting a warp wire will'be sufficientto support its share of the entire sunscreen under conditions-of normal usage; Such warp threadsmay be made-of colored or uncolored plastics as desired.

The two cooperating warp threadsof each warp wirev are located substantially in'planes, which are respectively perpendicular to the overall plane of the sunscreen. The said warp wires I2 are uniformly spaced and substantially parallel with: respect to each" other throughout the-v length of the sunscreenof 'Which they are aipart.

11110118: particular; preferred embodiment of the improved :warp wire: I2; as appearing in'Fig nres.v 1,2. and 3,..the two Warp threads of any: givenxpair; constitutingsaidwarp wire, may be of dissimilar shape and cross-section; The 'warp threads. on the one side of the louVerS areillustrated-by'therhalf round warp threads I3;'here louvers are here illustrated by a thin fiat strip 1 constituting. the said warp thread I4 which" passes over and'l'aroundeach louver II; as shownjinaFigure 3; therebytending to conform to the contour of said louvers in order to engage the straight, relatively stiffer warp thread It at point l8 between each pair of adjacent louvers. The extent of said contact area I8 is governed only by the amount necessary to hold the louvers H in proper, predetermined, fixed positions with respect to each other and the entire sunscreen. In one satisfactory embodiment of the sunscreen having bronze louvers 0.050 inch wide, 0.005 inch thick, and spaced of an inch apart, the warp wires are spaced one inch apart, are comprised of pairs of suitably designed nylon warp threads, and have a contact area approximately of an inch in length.

In a modification of the preferred embodiment of said improved warp wire. illustrated in Fig ures 4 and 5, the warp wire 28 may be com-prised of a pair of identically round, cooperating, contacting warp threads 2! and 22. As differentiated from warp threadsit and I l which constitute the warp wires E2, the said warp threads 2| and 22 of the warp wires 20 both bend around and tend to follow the contour of the plurality of horizontal louvers 23 which separate them. Consequently, said warp threads engage each other at 24 approximately midway between the adjacent louvers and substantially within a plane defined by the longitudinal centerlines of the said horizontal louvers.

As stated in connection with the warp wire l2 appearing in Figure 3, the extent of said engagement area 24 between the said warp threads 2! and 22 depends for the most part upon the amount of engagement necessary to hold the louvers 23 in proper predetermined, fixed positions with respect to each other, as well as the entire sunscreen, under normal conditions of use and treatment.

In one embodiment of this form of sunscreen, having horizontal louvers with dimensions and characteristics as mentioned above, nylon warp threads of .012 inch diameter proved satisfactory when contacting each other for approximately e% of an inch.

In order to produce a suitable bond between the cooperating warp threads of a warp wire, such as at the points 18 and 2% in the Figures 3 and 4, respectively, several conventional methods are available depending on the type of plastic used. For example, if thermoplastic materials are used for the warp threads, a heated pressure means of any convenient type, not shown, may be applied to those portions of either or both of the said warp threads which lie between the adjacent horizontal louvers, thereby first softening said parts and rendering them cohesive to each other, and then bringing them into contact with each other. Inasmuch as there is little or no resilience in the softened plastic, the engaged portions will remain in per manent engagement and without internal stresses after the heated pressure means is removed therefrom.

If soluble plastics are used for the warp threads, either or both of the opposing warp threads may be treated with a suitable solvent which will render them pliable and cohesive. A suitable pressure means is then applied to saidsoftened plastic until engagement as aforesaid is brought about between the said warp threads and permanent fixation therebetween is thereby accomplished.

Appropriate amounts of heat or solvent may also be applied to said warp threads or to the louvers themselves so as to cause the plastic of said warp threads to flow to a controlled extent about that portion of said louvers engaged by the warp threads. Such flow of the plastic will close anycracks between louvers and Warp threads through which rays of light may pass, as well as remove any internal stresses in the warp threads caused by their bending around the louver and cause them to grip the louver firmly.

The fabrication of sunscreens, with warp wires of plastic or a similar non-metallic substance eliminates any corrosion due to bimetallic electrolysis, along with its well known resultant disadvantages.

.It has been found in practice that there are certain optimum dimensions which may be applied to the type screen structure to which this invention relates without limiting the scope there- 01. Thus, it may be observed that the said vertical or warp wires may be advantageously from three-quarters of an inch to one inch or more apart, which structure will provide ample strength without blocking the passage of any appreciable amount of light or diminishing the flexibility of said sunscreen. It has also been observed that the centerline distance between adjacent louvers is advantageously approximately one-sixteenth of an inch. A sunscreen having these dimensions, of course, represents only one of many possible examples.

If as aforesaid the said warp threads, hence the warp wires, are made of an elastic plastic material, the resultant sunscreenfabric, containing the elastic warp wires, will be provided with a resilience which will increase its residual resistance to rough treatment and render it more suitable to some pecial applications such as rolled screen.

It may also be observed that the use of transparent plastics for said warp wires substantially reduces interference by the screen with free passage of indirect light between the horizontal louvers, which interference is virtually inevitable where warp wires are of metal as in the conventional type of completely metallic sunscreen presently in use.

It will be clearly understood that the foregoing descriptions and related drawings of specific embodiments of the improved type warp wire to which this invention rel-ates are given for purposes of illustration only, and it is not our intention, implied or otherwise, to eliminate other variations or modifications which do not depart from the scope of the invention unless specifically stated to the contrary in the hereinafter appended claims.

We claim:

1. A sunscreen panel having a plurality of similarly disposed, parallel, metallic louvers of elongated cross-section throughout their lengths and means holding said louvers in selected positions including a plurality of warp members arranged perpendicularly to the longitudinal axes 'of the louvers, the improvement in said means comprising: a plurality of spaced notches in at least one edge of each louver, the said corresponding notches in the several louver being vertically aligned with respect to each other; each warp member including a pair of warp threads of resilient, synthetic, organic material opposed to each other on opposite sides of the sunscreen panel and engaging said louvers at the opposite lateral edges thereof, the warp threads on the side of said louvers having the notches being received thereinto; the longitudinal cross sectional axis of each of said louvers extending transverselyabetween" said? warpthreads; said warp: threads'eontacting each other betweenaeach of: said louvers, saidwarp threads adhering to eachother bythe coalescence of the material thereof.

2;- Asunscreen panel having a plurality of-similarly-disposed, parallel, metallic louvers, of elorrgated' cross-section throughout their lengths and means including a plurality of warp members holding:v said louvers in selected positions: and arranged perpendicularly to the-longitudinal axes of the -1ouvers; the improvement in said means comprising: a plurality-of spacednotthesdnat least one edge of each louver, the said-correspending-notches-in'the'=several'louvers being vertically alignedwith respect toeachother'; a pair 15 of wrap" threads each" of resilient; synthetic, or'-=- ganic -material comprising one of said warpmembers; the longitudinal cross sectional axisof each of I said louvers extending transversely between said' warp' threads; one thread of eachofsaid vxiarp members" opposed to-the other on opposite sides of the sunscreen panel and engaging said louvers atthe opposite lateral edges thereof, thewarp threads on "the side of said 1ouvers-=-havin the notches received into said notches and flush" with the adjacent sides: of the louvers; and i'bOth'" of said warp threads of each of said warp members contacting each other 'between'each of said louvers', the area of' contacting including a WALKLEY: B. EW'ING; JOHN J. GREBE.

REFERENCES; CITED Thelfollowing references are of'record'inthe' file of this patent:

UNITED STATES. PATENTS. 

1. A SUNSCREEN PANEL HAVING A PLURALITY OF SIMILARLY DISPOSED, PARALLEL, METALLIC LOUVERS OF ELONGATED CROSS-SECTION THROUGHOUT THEIR LENGTHS AND MEANS HOLDING SAID LOUVERS IN SELECTED POSITIONS INCLUDING A PLURALITY OF WARP MEMBERS ARRANGED PERPENDICULARLY TO THE LONGITUDINAL AXES OF THE LOUVERS, THE IMPROVEMENT IN SAID MEANS COMPRISING; A PLURALITY OF SPACED NOTCHES IN AT LEAST ONE EDGE OF EACH LOUVER, THE SAID CORRESPONDING SEVERAL LOUVERS BEING VERTICALLY ALIGNED WITH RESPECT TO EACH OTHER; EACH WARP MEMBER INCLUDING A PAIR OF WARP THREADS OF RESILIENT, SYNTHETIC, ORGANIC MATERIAL OPPOSED TO EACH OTHER ON OPPOSITE SIDES OF THE SUNSCREEN PANEL AND ENGAGING SAID LOUVERS AT THE OPPOSITE LATERAL EDGES THEREOF, THE WARP THREADS ON THE SIDE OF SAID LOUVERS HAVING THE NOTCHES BEING 